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Old   July 17, 2013, 22:23
Question expansion factor in Ansa
  #1
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Jingyao Wang
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hi, i'm trying to simulate a oil splash in a gearbox due to the gear rotating. my the solve process could not continue, and i checked the output file. i noticed that the mesh statistic point out that the grid's expansion factor in some domain is "!", which means unacceptable.

in order to avoild this problem. when i generating the volume, i used the "tetra FEM". but the expansion problem is still there when i calculating.

i find out that there is no such quality criteria to check the expansion problem, and i do not know why there is an expansion problem.

would anyone have experience please help me? thank you!
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Old   July 27, 2013, 05:41
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Vangelis Skaperdas
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Hi There

Which ANSA version are you using?
Here are some suggestions

-Use MESHV>TETRA RAPID instead of TetraFEM it is much faster
-You should check for example Solid Fluent Skewness for 0.9 (an area with very abrupt expansion should also be bad in skewness too
-You can also check for Solid Growth Rate say 5

In any case the problem usually comes from bad quality shell mesh
Before MESHV check that you shell mesh has Fluent Skew<0.7 for example

Hope this helps

Vangelis


Quote:
Originally Posted by wjy-c View Post
hi, i'm trying to simulate a oil splash in a gearbox due to the gear rotating. my the solve process could not continue, and i checked the output file. i noticed that the mesh statistic point out that the grid's expansion factor in some domain is "!", which means unacceptable.

in order to avoild this problem. when i generating the volume, i used the "tetra FEM". but the expansion problem is still there when i calculating.

i find out that there is no such quality criteria to check the expansion problem, and i do not know why there is an expansion problem.

would anyone have experience please help me? thank you!
vangelis is offline   Reply With Quote

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